Granite Mountain–Speculator Mine Disaster

Shortly before midnight on 8 June 1917, an electrical cable was being lowered into the Granite Mountain shaft of the North Butte Mining Company when it caught fire deep underground. Flames, smoke and poisonous gases spread through a connected complex of workings, cutting off escape routes for miners on the night shift.

Rescuers entered the mine while trapped men constructed bulkheads and left written messages for their families. The disaster became the deadliest hard-rock mining accident in United States history and revealed the extreme risks created by deep mining, inadequate escape systems and the wartime demand for copper.

The fire occurred in a city already divided by corporate control, dangerous working conditions and labour militancy. It supports books about Butte’s mining communities, industrial disaster, rescue work, immigrant labour and the political unrest that followed the tragedy.